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Subject: Re: [RFC][v6][PATCH 0/9] clone_with_pids() syscall
From: Peter Zijlstra <peterz@infradead.org>
To: Arnd Bergmann <arnd@arndb.de>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>,
       linux-kernel@vger.kernel.org, Oren Laadan <orenl@cs.columbia.edu>,
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Date: Fri, 11 Sep 2009 13:40:05 +0200
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On Fri, 2009-09-11 at 13:34 +0200, Arnd Bergmann wrote:
> On Friday 11 September 2009, Peter Zijlstra wrote:

> > If you then get passed a longer clone_struct than you know about, all is
> > well IFF the tail is 0, otherwise fail with -E2BIG.
> > 
> > If you get passed a short clone_struct, zero out the tail.
> 
> I would leave out the size argument. We can put a few reserved fields
> and flag bits in there for possible extensions, but if we ever run out
> of these, just define a new syscall.

Why? If we can avoid this new syscall isn't that nicer?

> Also, if you're passing a struct, why not put nr_pids in there, and
> replace clone_pid_struct with a simple array? That would give us

Sure..